Examples of conventional sorting conveyor systems are disclosed, for example, in Japanese patent application Laid-open Nos. 144018/1983 and 53317/1984. In these prior art systems, a sorting conveyor is arranged to constitute a vertically endless loop; and take-out outlets for each forwarding destination are disposed along the horizontal path.
Thus, if there are a great number of destinations, the horizontal path must inevitably be long. However, there is a limitation in the length of the horizontal path as it requires a larger installation space. Consequently, should it become necessary to increase the number of outlets beyond the limitation, it is necessary to increase the number of the sorting conveyors themselves in order to increase the number of the horizontal paths.
However, according to such an arrangement, it is of course necessary to introduce articles to a particular conveyor such that the destinations of said articles may coincide with the destinations assigned to said particular conveyor. This would entail a troublesome preliminary sorting for each conveyor; and it is not possible to introduce articles having different destinations at random.